Research

Forests, especially structurally rich deciduous forests with old trees, are essential habitats for most native bat species. They serve as hunting grounds as well as summer and winter quarters. In Lower Austria, especially in the Weinviertel, there are such forests that have a high density of endangered species such as the Alcathoe bat, Bechstein's bat and Geoffroy's bat. However, intensive agriculture is fragmenting these habitats, threatening the genetic diversity and stability of bat populations. The project “From Isolation to Connectivity: Bats in Fragmented Forests” aims to promote habitat connectivity. In the Großweikersdorf model region, crucial structures are identified that ensure the connection between summer and winter quarters. Using telemetry, genetic analysis and connectivity analysis, movement patterns and networking structures are examined. Public relations work is intended to increase awareness of the need to protect bats and their habitats. The results of the project are intended to provide model solutions for other regions and contribute to the conservation of bat biodiversity.

Anthropogenic destruction of biosphere integrity is rapidly progressing. It even affects remote high mountain regions, questioning their role as biodiversity refuges in times of climate change. Although cold-determined alpine ecosystems are globally distributed, they are often very small-scale and fragmented, so that their disproportionally rich and unique vascular plant diversity is highly threatened through impacts of rising temperatures. This project will use the international GLORIA (https://gloria.ac.at) data set to understand changes in alpine plant diversity in summit zones that have been observed globally since the beginning of this century. By a worldwide compilation of standardised alpine vegetation data and integration of data on ecological drivers, the planned analyses deal with three main hypotheses: (1) changes in species numbers and composition are related to regional velocities of climate change, (2) combinations of reduced cold stress and increased drought stress accelerates loss of alpine plant diversity and (3) small-ranged species are overrepresented among declining and widespread ones among the gaining plants, being particularly worrisome in isolated small-scale alpine regions. We will use (1) data from repeated recordings of permanent plots, distributed over 100 alpine regions of the main mountain systems on Earth, combined with (2) remote sensing data of topography, changes in vegetation greenness and snow cover, (3) in situ-measured soil temperature and gridded climate data series as well as (4) data of species’ overall distribution and their thermic and hydrological niches in order to analyse and assess the magnitude and rates of biodiversity changes in relation to the main drivers.

In recent years, the use of terrestrial laser scanners (TLS) and airborne laser scanning (ALS) to characterize forests has made considerable progress and can be used both to record individual trees and thus biomass and carbon stocks and to monitor changes (growth, turnover). In evergreen tropical forests, such evaluations face the challenge that it is not possible to measure in a leafless state, which limits the view of trunks and branches and thus makes it difficult to calculate trunk sizes. In 2024, LIDAR surveys were carried out in La Gamba, Costa Rica, in primary, secondary forests and reforestation areas with planted trees using modern TLS and ALS systems. These data are to be analyzed as part of the project. First, individual TLS scans must be linked and the trees segmented, then these results will be checked with direct measurements of the trees on site and, as far as possible, the allometric model used for biomass calculation will be improved.